In this work, we developed a roll‐to‐roll printed poly(3,4‐ethylenedioxythiophene)/polystyrene sulphoanate without graphene oxide (GO) (PEDOT/PSS) and with graphene oxide (PEDOT/PSS/GO) plastic films for the electrochemical determination of carbofuran. Both the PEDOT/PSS and PEDOT/PSS/GO plastic films showed electroactivity towards the oxidation of carbofuran. Incorporation of graphene oxide (GO) improves the electrochemical activity of carbofuran and increased its sensitivity. The printed plastic films were characterized by cyclic voltammetry (CV), linear sweep voltammetry (LSV), surface profilometer, four point probe and atomic force microscopy (AFM). The effects of pH, deposition time, deposition potential and film thickness on the oxidation peak current of carbofuran were investigated. Under the optimized conditions, a dynamic linear range of 1 μM–90 μM with a detection limit of 1.0×10?7 M (S/N=3) were obtained. The printed PEDOT/PSS/GO plastic electrode was applied for the determination of carbofuran in vegetable and fruit samples with recoveries between 94.4 and 101.8 %. 相似文献
The synthesis, structural characterization, and electrochemical properties of a series of isotruxene–polyaniline (PANI ) hybrid systems (SITPs , SITAs , and CITs ) are reported. The syntheses were performed by in situ chemical oxidative polymerization of aniline in the presence of isotruxene additives ITP and/or ITA at specific aniline‐to‐additive molar ratios. The polymers SITPs and SITAs display granular morphology, but for the polymers CITs a spherical morphology with a diameter of 300–500 nm is found. These hybrid systems display electrochemical capacitive performance superior to those of the parent PANI prepared under the same condition (e.g., 385–463 vs. 181 F/g at 3 mA /cm2 current density during charge–discharge test). Molecular (star‐shaped or hyperbranched vs. linear topology) and supramolecular (isotruxene–PANI π–π and cation–π interactions) models in accounting for the observed morphology and electrochemical properties are provided. 相似文献
Surface‐modified thermally expandable microcapsules (TEMs) hold potential for applications in various fields. In this work, we discussed the possible surface coating mechanism and reported the properties of TEMs coated with polyaniline (PANI) and polydisperse graphene oxide sheets (ionic liquid‐graphene oxide hybrid nanomaterial (ILs‐GO)). The surface coating of PANI/ ILs‐GO increased the corresponding particle size and its distribution range. The morphologies analyzed by scanning electron microscopy indicated that no interfacial gap was observed between the microspheres ink and substrate layer during the substrate application. The thermal properties were determined by thermogravimetric and differential thermal analyses. The addition of ILs‐GO to the polyaniline coating significantly improved the thermal expansion and thermal conductivity of the microcapsules. The evaporation of hexane present in the core of TEMs was not prevented by the coating of PANI/ ILs‐GO. The printing application of TEMs showed excellent adaptability to various flexible substrates with great 3D appearance. By incorporating a flame retardant agent into TEMs coated by PANI/ILs‐GO, finally, these TEMs also demonstrated a great flame retardant ability. We expect that these TEM‐coated PANI/ ILs‐GO are likely to have the potential to improve the functional properties for various applications. 相似文献
The effects of electrostatic forces (EF), control on the morphology, structure, and electrochemical properties of polyaniline, PANI/graphene oxide (GO), nanocomposites prepared by interfacial electropolymerization (IEP), are studied in this work. FESEM images showed that the IEP method can form the PANI/GO nanocomposites when the EF-control has been found mainly on the PANI nanofibers formation and growth on the GO film surface; and the EF-enhancement can form PANI nanofibers with small nano-diameter, longer length, uniform morphology, high order and well orientation as compared with the EF-reduction-formed sample. The EF-enhancement-formed PANI/GO nanocomposite showed improved electrochemical properties than that of the EF-reduction-formed sample due to the EF-enhancement that enhances the C–N structure for PANI/GO nanocomposite. 相似文献
The polyaniline/TiO2/graphene oxide (PANI/TiO2/GO) composite, as a novel supercapacitor material, is synthesized by in situ hydrolyzation of tetrabutyl titanate and polymerization of aniline monomer in the presence of graphene oxide. The morphology, composition and structure of the composites as-obtained are characterized by SEM, TEM, XRD and TGA. The electrochemical property and impedance of the composites are studied by cyclic voltammetry and Nyquist plot, respectively. The results show that the introduction of the GO and TiO2 enhanced the electrode conductivity and stability, and then improved the supercapacitive behavior of PANI/TiO2/GO composite. Significantly, the electrochemical measurement results show that the PANI/TiO2/GO composite has a high specific capacitance (1020 F g−1 at 2 mV s−1, 430 F g−1 at 1 A g−1) and long cycle life (over 1000 times). 相似文献
We demonstrate a high surface area of manganese sulfide (MnS) nanoparticles via a simple solution method and investigated its morphology, physicochemical, and electrochemical studies. For the first time, we attempted to exploit the polymerization of aniline without adding HCl, as it is corrosive to the metal sulfide. Instead, the acidic group present on the graphene oxide surface plays a significant role to some extent as an acidic dopant in the polymerization process. This in-situ polymerization results in the uniform coverage of granular PANI on the entire MnS/GO nanocomposite, which enhances the interfacial interactions between PANI and MnS/GO nanoparticles. The introduction of graphene oxide (GO) to pristine MnS improved the specific capacitance, surface area, and average pore size. And incorporating PANI to MnS/GO leads to an increase in the interfacial interaction between the different pore sized nanoparticles giving enhanced specific capacitance. The specific capacitance for MnS/GO/PANI nanocomposite as measured by galvanostatic charge-discharge measurements was found to be 773 F/g at 1 A/g current density, and even at higher current density, it showed a specific capacitance of 484 F/g at 3.8 A/g. The specific capacitance obtained for MnS/GO/PANI nanocomposite from CV shows 822 F/g at 10 mV/s and 315 F/g at 200 mV/s. The combinatorial effects without destroying the metal sulfide nanostructure can provide an alternate route to design, promising electroactive nanocomposites is an ideal choice as a cost-effective, next-generation high-performance supercapacitor application. 相似文献
Interactions between the π bonds in the aromatic rings of polyaniline (PANI) with carbon nanostructures (CNs) facilitate charge transfer between the two components. Different types of phenyleneamine‐terminated CNs, including carbon nano‐onions (CNOs) and single‐walled and multi‐walled carbon nanotubes (SWNTs and MWNTs, respectively), were prepared as templates, and the CN/PANI nanocomposites were easily prepared with uniform core–shell structures. By varying the ratio of the aniline monomers relative to the CNs in the in situ chemical polymerization process, the thickness of the PANI layers was effectively controlled. The morphological and electrical properties of the nanocomposite were determined and compared. The thickness and structure of the PANI films on the CNs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and infrared spectroscopy. TEM and SEM revealed that the composite films consisted of nanoporous networks of CNs coated with polymeric aniline. The electrochemical properties of the composites were investigated by cyclic voltammetry and electrochemical impedance spectroscopy. These studies showed that the CN/PANI composite films had lower resistance than pure polymeric films of PANI, and the presence of CNs much improved the mechanical stability. The specific electrochemical capacitance of the CNO/PANI composite films was significantly larger than for pure PANI. 相似文献
The surface of a stainless steel fiber was made larger, porous and cohesive by platinizing for tight attachment of its coating. Then it was coated by a polyaniline/polypyrrole/graphene oxide (PANI/PP/GO) nanocomposite film using electrochemical polymerization. The prepared PANI/PP/GO fiber was used for headspace solid‐phase microextraction (HS‐SPME) of linear aliphatic aldehydes in rice samples followed by GC‐FID determination. To achieve the highest extraction efficiency, various experimental parameters including extraction time and temperature, matrix modifier and desorption condition were studied. The linear calibration curves were obtained over the range of 0.05–20 μg g−1 (R 2 > 0.99) for C4–C11 aldehydes. The limits of detection were found to be in the range of 0.01–0.04 μg g−1. RSD values were calculated to be <7.4 and 10.7% for intra‐ and inter‐day, respectively. The superiority of the prepared nanocomposite SPME fiber was established by comparison of its results with those obtained by polydimethylsiloxane, carbowax–divinylbenzene, divinylbenzene–carboxen–polydimethylsiloxane and polyacrylate commercial ones. Finally, the nanocomposite fiber was used to extract and determine linear aliphatic aldehydes in 18 rice samples. 相似文献
A new polyaniline (PANI)‐functionalized graphene oxide (GO‐PANI) was prepared by using an in situ oxidative graft polymerization of aniline on the surface of GO. Its highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), ionization potential (IP), and electron affinity (EA) values experimentally estimated by the onset of the redox potentials were ?5.33, ?3.57, 5.59, and 3.83 eV, respectively. A bistable electrical‐switching effect was observed in electronic device with the GO‐PANI film sandwiched between the indium tin oxide (ITO) and Al electrodes. This device exhibited two accessible conductivity states, that is, the low‐conductivity (OFF) state and the high‐conductivity (ON) state, and can be switched to the ON state under a negative electrical sweep, and can also be reset to the initial OFF state by a reverse (positive) electrical sweep. The ON state is nonvolatile and can withstand a constant voltage stress of ?1 V for 3 h and 108 read cycles at ?1 V under ambient conditions. The nonvolatile nature of the ON state and the ability to write, read, and erase the electrical states, fulfill the functionality of a rewritable memory. An ON/OFF current ratio of more than 104 at ?1 V achieved in this memory device is high enough to promise a low misreading rate through the precise control of the ON and OFF states. The mechanism associated with the memory effects was elucidated from molecular simulation results. 相似文献
Multi-walled carbon nanotube (MWNT)/polyaniline (PANI) composite films with good uniformity and dispersion were prepared by electrochemical polymerization of aniline containing well-dispersed MWNTs. The results of transmission electron microscopy (TEM) show that aniline can be used to solve MWNTs via formation of donor–acceptor complexes. Scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) revealed that the well arrangement of PANI-coated MWNTs in these films facilitated improved electron and ion transfer relative to pure PANI films and this may be due to the strong interaction between MWNTs and PANI. 相似文献
In order to explore the effect of graphene surface chemistry on electrochemical performance based on polyaniline–graphene hybrid material electrodes, four different polyaniline–graphene nanocomposites were fabricated with graphene oxide, reduced graphene oxide, aminated graphene and sulfonated graphene as carriers, respectively. The nanocomposites feature various structures and morphologies, which could be used to more deeply understand the morphology and structure effects caused by surface chemistry on electrochemical performance. The experimental results reveal that functionalized electronegative graphene was conducive to the vertical and neat growth of polyaniline (PANI) nanorods. The array architecture endowed the PANI–GS nanocomposite with a large ion‐accessible surface area and high‐efficiency electron‐ and ion‐transport pathways. Meanwhile, the introduction of sulfonic acid functional groups accelerated the redox reaction with doping and dedoping of the PANI. Thereby, the PANI–GS nanocomposite exhibited a high specific capacitance of 863.2 F g?1 at a current density of 0.2 A g?1 and the excellent rate capability of 67.4 % (581.6 F g?1 at 5 A g?1), which were much better than the other three nanocomposites produced. 相似文献
A hybrid material consisting of bulk-reduced TiO2, graphene oxide (GO) and polyaniline (PANI) was fabricated by decorating TiO2 with GO, followed by in-situ oxidative chemical polymerization of aniline. The TiO2 nanoparticles (NPs) with thermally stable bulk reduction states were initially prepared from porous amorphous titanium as the precursor. The TiO2 NPs and GO were chemically conjugated to each other via amide bonds to improve the stability of the composite. The sensor, if operated in the conductivity mode, exhibits strong signal changes, and fast response and recovery times (of 32 and 17 s, respectively) to gaseous ammonia even at room temperature. Its response range extends from 5 to 300 ppm, and the lower detection limit is 5 ppm. The sensor is fairly selective and not interfered by gases such as CO, CH4, and trimethylamine, and by vapors of methanol and ethanol. It also displays good temporal stability. This is attributed to the bulk-reduced state of TiO2, the presence of oxygen functional groups on GO, and the strong adsorption and rapid diffusion of ammonia. The results also imply the presence of a synergetic effect between TiO2 and GO/PANI, which is probably beneficial for the potential application of the resulting composite as a gas sensor.
Graphical abstract A hybrid material consisting of bulk-reduced TiO2, graphene oxide (GO) and polyaniline (PANI) was fabricated by decorating TiO2 with GO, followed by in-situ oxidative chemical polymerization of aniline. The TiO2/GO/PANI sensor exhibits strong signal changes, fast response time (32 s) and recovery time (17 s) to ammonia at room temperature. It also displays good selectivity and temporal stability.
In the present work, a set of polyaniline–graphene oxide (PANI–GO) nanocomposites which exhibit superior properties in terms of shelf life, processability and conductivity due to the synergistic effect of GO and PANI, have been synthesized by varying the concentration of highly non-conducting GO with respect to aniline. The obtained materials were characterized by UV–Vis, FTIR, XRD, Raman, TGA as well as FESEM, TEM analysis. The results reveal that nanocomposites show better dispersibility, crystallinity, thermal stability, and conductivity. Further, the synthesized composites have been tested for their anti-corrosion properties. The potentiodynamic results reveal that PANI nanocomposites with 1% GO exhibited long-term anti-corrosion behavior with a corrosion rate of 6.5 × 10?5 mm year?1, which is much lower than its individual components and commercial-grade red oxide. Also, it possesses highest impedance modulus ~33 kΩ cm2 and real impedance ~32 kΩ cm2, maximum coating resistance ~14.81 × 103 Ω cm2 and minimum coating capacitance after 96 h of immersion in 3.5% mass NaCl than those exhibited by all other coated samples. Higher concentration of GO could not retard the corrosion rate confirming that hydrophilicity of GO play an important role in the redox mechanism of PANI. 相似文献
Graphene/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin multilayer films composed of graphene sheet (GS) and mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (NH2‐β‐CD) were fabricated easily by two steps. First, negatively charged graphene oxide (GO) and positively charged mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (NH2‐β‐CD) were layer‐by‐layer (LBL) self‐assembled on glassy carbon electrode (GCE) modified with a layer of poly(diallyldimethylammonium chloride) (PDDA). Then graphene/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (GS/NH2‐β‐CD) multilayer films were built up by electrochemical reduction of graphene oxide/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (GO/NH2‐β‐CD). Combining the high surface area of GS and the active recognition sites on β‐cyclodextrin (β‐CD), the GS/NH2‐β‐CD multilayer films show excellent electrochemical sensing performance for the detection of DA with an extraordinary broad linear range from 2.53 to 980.05 µmol·L?1. This study offers a simple route to the controllable formation of graphene‐based electrochemical sensor for the detection of DA. 相似文献
The homogeneous polyaniline–graphene oxide (PANI-GO) nanocomposites were facilely assembled with a redox system in which cumene hydroperoxide (CHP) and iron dichloride (FeCl2) acted as oxidant and reductant, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images showed that PANI scales coated uniformly on the surface of GO sheets owing to the synergistic effect between the PANI and GO. The obtained PANI-GO nanocomposites exhibited improved electrochemical performance as an electrode material for supercapacitors compared with the pure PANI. The specific capacitance of the PANI-GO nanocomposites was high up to 308.3 F g?1, much higher than that of the pure PANI with specific capacitance of 150 F g?1 at a current density of 1 A g?1 in 2 M H2SO4 electrolyte. The Raman and XPS results illustrated that enhanced electrochemical performance might be attributed to the π-π conjugation between the PANI and GO sheets. 相似文献